v3.21.2
Loans - Summary of Consumer Loans by Refreshed FICO Credit Score (Detail) - USD ($)
$ in Millions
9 Months Ended 12 Months Ended
Sep. 30, 2021
Dec. 31, 2020
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 146,956 $ 119,989
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 100.00% 100.00%
FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 9,700 $ 8,093
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 100.00% 100.00%
Installment [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 3,449 $ 3,823
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 100.00% 100.00%
Installment [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
2021 and 2020 $ 1,399 $ 1,359
2020 and 2019 856 1,357
2019 and 2018 732 942
2018 and 2017 403 158
2017 and 2016 57 7
2016 2  
Total loans, gross $ 3,449 $ 3,823
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 100.00% 100.00%
Credit card [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 6,251 $ 4,270
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 100.00% 100.00%
Credit card [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 6,251 $ 4,270
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 100.00% 100.00%
Greater than or equal to 660 [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 7,915 $ 6,870
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 82.00% 85.00%
Greater than or equal to 660 [Member] | Installment [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
2021 and 2020 $ 1,380 $ 1,321
2020 and 2019 816 1,225
2019 and 2018 658 792
2018 and 2017 347 128
2017 and 2016 47 6
2016 2  
Total loans, gross $ 3,250 $ 3,472
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 94.00% 91.00%
Greater than or equal to 660 [Member] | Credit card [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 4,665 $ 3,398
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 75.00% 80.00%
Less than 660 [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 1,785 $ 1,223
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 18.00% 15.00%
Less than 660 [Member] | Installment [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
2021 and 2020 $ 19 $ 38
2020 and 2019 40 132
2019 and 2018 74 150
2018 and 2017 56 30
2017 and 2016 10 1
Total loans, gross $ 199 $ 351
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 6.00% 9.00%
Less than 660 [Member] | Credit card [Member] | FICO [Member]    
Financing Receivable, Recorded Investment [Line Items]    
Total loans, gross $ 1,586 $ 872
Percentage concentration of gross installment and credit card loans by refreshed FICO credit score 25.00% 20.00%